Tapping-machine.



PATENTED NOV. 8, 1904.

G. A. HOFFMAN.

TAPPING MACHINE.

APPLICATION FILED APR. 9, 1904.

4 SHEETS-SHEET 1.

N0 MODEL.

INVENTOR g haw ATTORNEY.

No. 774,357. I PATBNTED'NOV. 8, 1904.

G. A. HOFFMAN.

TAPPING MACHINE.

APPLICATION XILED APR. 9, 1904.

N0 MODEL. 4SHEE'IS-SHEET 2.

WITNESSES IN YE N TOR A TTORNEY.

PATENTED NOV. 8. 1904.

G. A. HOFFMAN.

TAPPING MACHINE.

APPLICATION FILED APR. 9, 1904 4 SHEBTSSHEET 3.

NO MODEL.

jaa

iiilHL yaw L [NYE/ T05 g fWm RY D fl ATTORNEY.

No. 774,357. PATENTEDNOV. 8, 1904.

G. A. HOFFMAN.

TAPPING MACHINE.

APPLICATION FILED APR. 9, 1904.

4 SHEETS-SHEET 4.

N0 MODEL.

Kb ZN INVENTOR A TTORNEV.

I UNITED STATES:-

Patented November 8, I904.

PATENT OFFICE.

GEORGE A. HOFFMAN, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO HUGO BILGRAM, OF PHILADELPHIA, PENNSYLVANIA.

MACHINE.

SPECIFICATION forming part of Letters Patent No. 774,357, dated November 8, 1904.

Application filed April 9, 1904.

To all whom, it may con/c0772]:

Be it known that I. GEORGE A. HOFFMAN, a citizen of the United States, and a resident of the city and county of Philadelphia, State of Pennsylvania, have invented certain new and useful Improvements in Tapping-Machines, of which the following is a specification.

My invention relates to improvements in machines for tapping nuts or similar articles; and the object of my invention is to furnish an automatic tapping-machine in which the tap will be continuously rotated in one direction.

In the accompanying drawin s, forming part of this specification, and in which similar characters of reference indicate similar parts throughout the several views, Figure 1 is a plan of my tapping-machine ora view of Fig. 2 looking in the direction of the arrow'in this figure; Fig. 2, a side elevationof my tappingmachine; Fig. 3, a section, enlarged, of Fig. 2 on line 3 3; Fig. 4, a section, enlarged, of Fig. 2 on line 1 4; Fig, 5, a central sectional elevation through the blank-conveyer, taken on line 5 5, Fig. 6; Fig. 6, a section of Fig. 5 on line 6 6; Figs. Tand 8, perspective views of a nut before and after threading; Fig. 9, a section corresponding to the section shown in Fig. 3 of a modification of my machine; Fig. 10, a section of Fig. 9 on line 10 10; Fig. 11, aperspective view of tap-holder, Fig. 9; Fig. 12, a section of Fig. 9 on line 11 11.

a is the frame of my machine; 6, a drivingpulley which drives a shaft 0, which carries a bevel-gear (Z, which drives a bevel-gear e, which is carried on a shaft f.

Fast upon shaft f are the gears g Zr, which gear, respectively, with the gears Z j, which are carried the first by a shaft Z), the second by a shaft Z.

m is a worm carried by shaft f; n, a wormwheel gearing with worm m.

0 represents collars carried by shaft is; p, collars carried by shaft Z.

r is a lever pivoted at s, the upper end of which is bifurcated and engages collars 0; t, a lever pivoted at a, the upper end of which is bifurcated and engages collars p.

l is a pin carried by lever 1 2, a pin car- Serial No- 202,337. (No model.)

3 1 are arms one end of each of which is pivoted to the worm-wheel a at 5, the other ends being slotted, as shown at 6 7, Fig. 2. The pins 1 2, carried by levers r t, pass, respectively, through slots 6 7.

' 8 is a spring connecting levers 1 Z.

9 is a tap the ends of which are squared and adapted to be engaged by sockets 1O 11 in the ends, respectively, of shafts 70 Z.

12 is a guide, in the present case stationary, which holds the nut-blanks 13 from turning while being operated upon by the tap.

14 is a magazine from which the nuts are fed to the guide 12.

The operationof the machine is as follows: The blanks 13 are fed to the magazine 14. in any suitable manner and fall from this guide to the guide 12, being prevented from entering this latter guide until the proper time by theend of the shaftlawhioh enters one end of the guide 12, as shown in Fig. 3. The pulley Z, beingdriven, drives, through shaft'c, the bevel-gear (Z, which drives bevel-gear e, which drives shaft f. The shaft f drives the gears g 71, which drive the gears Z j, which drive the shafts 70 Z, the sockets 1O 11 in these shafts driving the tap 9. IVith the rotation of shaft f is rotated the worm m, which drives'the worm-wheel a, the rotation of which causes, through arms 3 4:, the alternate rocking of the arms 0 t, which disconnect alternately the shafts in Z from the tap 9, the shafts is Z being free to slide in their hearings in frame a and the gears Z 1' being secured to their respective shafts by splines 15, so that the shafts may also slide through these gears. When the arm 1" is rocked out, its bifurcated upper end engages the outer collar 0 on shaft is and moves this shaft out until its inner end is completely clear of the end of the tap 9 and until a sufficient space is left between the end of the tap and the end of the shaft is for the entrance of a blank from the magazine 14. In the meantime the tap is rotated by the shaft Z, the socket 11 of which remains engaged by the squared end of the tap. A blank having entered the guide 12 from the magazine 14 and the wheel at having been moved so as to allow ried by lever t.

turns the arm 9' to its first position, thereby moving in the shaft in, which pushes the blank just entered in guide 12 upon the tap 9, cansing the shaft It; to operatively engage the tap. After the inner collar 0 abuts against the frame a, Fig. 3, the arm 1' will remain at rest, the slot 6 permitting the arm 3 to follow the movement of the pin 5 of the worm-wheel a. A further movement of the wheel 71 causes the arm 4 to push out the lever 25, which moves the shaft Z out of engagement with the tap 9, permitting a blank that may have been threaded to fall down between the end of the tap and the end of this shaft. A further movement of the wheel it causes the arm 4: to release the lever t, and the spring 8 returns this latter lever and the shaft Z to their first positions.

In practice the shaft f and connected parts are inclined, as shown in Fig. 2, so as to facilitate the discharge of the tapped blanks from the tap. The tap is prevented from falling from place when the shaft Z is moved out of contact with it by the turning tap engaging the blanks within the guide 12. These several parts coaeting as a result of the friction of the nuts 13 against the guide 12 crowd the tap against the upper shaft k.

It will be observed that the tap is constantly rotated in one direction by either one or the other, or by both, of the shafts 7c Zand that the blanks 13 are constantly fed to and discharged from the tap.

In Figs. 9 to 12 a modification of my device is shown, in which the tap is held from rotation alternately by rods in" Z, which longitudinally are movable, but which do not rotate, the guide 12 surrounding the tap being the rotatable member instead of the fixed member as before shown and described.

In the modification the guide 12 is carried in a sleeve 16 and carries a gear-wheel 17,

driven by a gear-wheel 18 on the shaftf. In other respects the modification is substantially similar in construction to that already described. This modification is what is known in kinematics as an inversion, the tap being rotated relatively to the guide by the rotation of the guide.

Having thus described my invention, I claim as new and desire to secure byLetters Patent 1. In combination, a tap having ends adapted to be engaged by sockets, socketed shafts adapted to alternately engage the opposite ends of said tap, means for carrying said shafts, means for alternately moving said shafts into and out of engagement with said tap, a blank-guide surrounding said tap, and means for rotating said tap relatively to said guide.

2. In combination, a tap having ends adapt-- ed to be engaged by sockets, socketed shafts adapted to alternately engage the opposite ends of said tap, means for carrying said shafts, means for alternately moving said shafts into and out of engagement with said tap,a blank-guide surrounding said tap, means for rotating said tap relatively to said guide, and means for feeding blanks to said guide.

3. In combination, a tap having ends adapted to be engaged by sockets, socketed shafts adapted to alternately engage the opposite ends of said tap, said shafts and tap being inclined, means for carrying said shafts, means for alternately moving said shafts into and out of engagement with said tap, a blankguide surrounding said tap, and means for rotating said tap relatively to said guide.

GEORGE A. HOFFMAN.

WVitnesses:

MORTIMER A. J ONES, ISAAC THOMPSON. 

